    jQuery.extend({
       

        createUploadIframe: function(id, uri)
       {
             //create frame
                var frameId = 'jUploadFrame' + id;
                var iframeHtml = '<iframe id="' + frameId + '" name="' + frameId + '" style="position:absolute; top:-9999px; left:-9999px"';
             if(window.ActiveXObject)
             {
                    if(typeof uri== 'boolean'){
                   iframeHtml += ' src="' + 'javascript:false' + '"';

                    }
                    else if(typeof uri== 'string'){
                   iframeHtml += ' src="' + uri + '"';

                    }   
             }
             iframeHtml += ' />';
             jQuery(iframeHtml).appendTo(document.body);

                return jQuery('#' + frameId).get(0);         
        },
        createUploadForm: function(id, fileElementId)
       {
          //create form   
          var formId = 'jUploadForm' + id;
          var fileId = 'jUploadFile' + id;
          var form = jQuery('<form  action="" method="POST" name="' + formId + '" id="' + formId + '" enctype="multipart/form-data"></form>');   
          var oldElement = jQuery('#' + fileElementId);
          var newElement = jQuery(oldElement).clone();
          jQuery(oldElement).attr('id', fileId);
          jQuery(oldElement).before(newElement);
          jQuery(oldElement).appendTo(form);
          //set attributes
          jQuery(form).css('position', 'absolute');
          jQuery(form).css('top', '-1200px');
          jQuery(form).css('left', '-1200px');
          jQuery(form).appendTo('body');      
          return form;
        },

        ajaxFileUpload: function(s) {
            // TODO introduce global settings, allowing the client to modify them for all requests, not only timeout      
            s = jQuery.extend({}, jQuery.ajaxSettings, s);
            var id = new Date().getTime()       
          var form = jQuery.createUploadForm(id, s.fileElementId);
          var io = jQuery.createUploadIframe(id, s.secureuri);
          var frameId = 'jUploadFrame' + id;
          var formId = 'jUploadForm' + id;      
            // Watch for a new set of requests
            if ( s.global && ! jQuery.active++ )
          {
             jQuery.event.trigger( "ajaxStart" );
          }           
            var requestDone = false;
            // Create the request object
            var xml = {}   
            if ( s.global )
                jQuery.event.trigger("ajaxSend", [xml, s]);
            // Wait for a response to come back
            var uploadCallback = function(isTimeout)
          {         
             var io = document.getElementById(frameId);
                try
             {            
                if(io.contentWindow)
                {
                    xml.responseText = io.contentWindow.document.body?io.contentWindow.document.body.innerHTML:null;
                        xml.responseXML = io.contentWindow.document.XMLDocument?io.contentWindow.document.XMLDocument:io.contentWindow.document;
                   
                }else if(io.contentDocument)
                {
                    xml.responseText = io.contentDocument.document.body?io.contentDocument.document.body.innerHTML:null;
                       xml.responseXML = io.contentDocument.document.XMLDocument?io.contentDocument.document.XMLDocument:io.contentDocument.document;
                }                  
                }catch(e)
             {
                jQuery.handleError(s, xml, null, e);
             }
                if ( xml || isTimeout == "timeout")
             {            
                    requestDone = true;
                    var status;
                    try {
                        status = isTimeout != "timeout" ? "success" : "error";
                        // Make sure that the request was successful or notmodified
                        if ( status != "error" )
                   {
                            // process the data (runs the xml through httpData regardless of callback)
                            var data = jQuery.uploadHttpData( xml, s.dataType );   
                            // If a local callback was specified, fire it and pass it the data
                            if ( s.success )
                                s.success( data, status );
       
                            // Fire the global callback
                            if( s.global )
                                jQuery.event.trigger( "ajaxSuccess", [xml, s] );
                        } else
                            jQuery.handleError(s, xml, status);
                    } catch(e)
                {
                        status = "error";
                        jQuery.handleError(s, xml, status, e);
                    }

                    // The request was completed
                    if( s.global )
                        jQuery.event.trigger( "ajaxComplete", [xml, s] );

                    // Handle the global AJAX counter
                    if ( s.global && ! --jQuery.active )
                        jQuery.event.trigger( "ajaxStop" );

                    // Process result
                    if ( s.complete )
                        s.complete(xml, status);

                    jQuery(io).unbind()

                    setTimeout(function()
                               {   try
                                  {
                                     jQuery(io).remove();
                                     jQuery(form).remove();   
                                     
                                  } catch(e)
                                  {
                                     jQuery.handleError(s, xml, null, e);
                                  }                           

                               }, 100)

                    xml = null

                }
            }
            // Timeout checker
            if ( s.timeout > 0 )
          {
                setTimeout(function(){
                    // Check to see if the request is still happening
                    if( !requestDone ) uploadCallback( "timeout" );
                }, s.timeout);
            }
            try
          {

             var form = jQuery('#' + formId);
             jQuery(form).attr('action', s.url);
             jQuery(form).attr('method', 'POST');
             jQuery(form).attr('target', frameId);
                if(form.encoding)
             {
                jQuery(form).attr('encoding', 'multipart/form-data');               
                }
                else
             {   
                jQuery(form).attr('enctype', 'multipart/form-data');         
                }         
                jQuery(form).submit();

            } catch(e)
          {         
                jQuery.handleError(s, xml, null, e);
            }
          
          jQuery('#' + frameId).load(uploadCallback   );
            return {abort: function () {}};   

        },

        uploadHttpData: function( r, type ) {
            var data = !type;
            data = type == "xml" || data ? r.responseXML : r.responseText;
            // If the type is "script", eval it in global context
            if ( type == "script" )
                jQuery.globalEval( data );
            // Get the JavaScript object, if JSON is used.
            if ( type == "json" )
                eval( "data = " + data );
            // evaluate scripts within html
            if ( type == "html" )
                jQuery("<div>").html(data).evalScripts();

            return data;
        }
    })